Linear alteration of underfoot surfaces is a common construction and maintenance task that, using conventional technology, tends to be unduly cumbersome. For example, a project involving painting lines on pavement to delineate parking spaces using conventional technology is likely to begin with a time-consuming layout process. In a particular example of such a process, a crew first marks beginning and ending points of each line to be painted. Next, the crew affixes a string at one of the beginning and ending points of a given line. The crew then affixes the string at the other of the beginning and ending points of the given line. When the string is taut, the crew presumes it to be an accurate representation of a straight path between the beginning and ending points of the given line. The crew then marks the path based on the position of the string and repeats the same process for each of the remaining lines to be painted. To mark the path, the crew may, for example, either “snap” the line to leave behind a chalk marking or walk along the path and paint dashes, dots, or other indications of the path at intermittent positions along the length of the string. Finally, the crew uses the mark or marks to guide movement of a paint-striping machine that applies paint along the path. As discussed below, this approach to painting lines and other approaches to the same and other types of linear alteration of underfoot surfaces have certain limitations and/or disadvantages. Accordingly, there is a need for innovation in this field.